Centrifugal pump



Feb. 18, 1947. J. B. WADE 41mm CENTRIFUGAL' PUMP Filed Jan. 5l, 1942 2 Sheets-Sheet -2 the pump per se.

Patented Feb.. 18, 1947 N UNITED, sT

CENTRIFUGAL John B. Wade, Hamilton, Ohio, assignon-by mesne assignments, to Food Machinery Corporation, a corporation Application January 31, 194.2, Serial No. 429,097

. 1 l 'This invention.k relates to improvements in centrifugal pumps and particularly to such pumps as are employed for pumping liquids having occluded vapor, or air or other gases.

When a centrifugal pump is operating under such conditions it is necessary to separate the occluded vapor and gases from the liquid before the latter is admitted to the pump or the vapor and gases will accumulate and pocket within the admission chamber of the pump forming a socalled vapor or gas lock which materially interferes with the proper operation of the pump.

Heretofore lt has been the practice to build pumps intended for operating under such conditions as an integral part of the tank containing the liquid to be pumped, the pump being a part of the tank bottom. A vortex in the liquid was then produced and maintained by mounting the pipe introducing the liquid into the tank tangentially. I have observed that the cost of manufacturing pumps operatingon this general plan for handling liquids with occluded vapors and gases is relatively1 high.

It is an object of my invention to produce a relativelyA inexpensive pump unit for pumping liquids having occluded vapors and gases.

' serted into a tank and suspended from above therein so as t operate near the bottom of the tank to pump liquid lfrom the tank and separate occluded vapors and gases from the liquid before. the latter is admitted to the pump. 1

It is a still further object of the present invention to provide a novel and eflicient device for separating occluded vapors and gases from a liquid during lthe delivery of the latter to the impeller of a centrifugal pump. I

The manner of accomplishing the foregoing objects as well as further objects and advantages will be made apparent in the` following description taken in connection with the accompanying drawing, in which:

Fig. 1 is a vertical sectional viewof a tank having a, preferred embodiment of the invention in-y stalled therein.

' Fig. 2 is an enlarged detail sectional view ofV Fig. 3 is a horizontal section l view taken on the line 3-3 of Fig. 2.` l

3 Claims. (Cl. 103-113) y 2 Fig. 4 ls a horizontal the line 6--6 of Fig. 2.

Referring specically to the drawings, my in vention is there shown'as embodied in a pump unit Ill which is mounted in a tank il for the purpose of separating occluded vapors and gases from liquid contained in said tank and pumping said liquid from the tank'. VThe unit Ill may include a motor base i2 supported on the tank ii about an opening i3 in an upper vWall thereof. The base l2 may support a motor it having a shaft l5 which is connected by a coupling it to a line shaft i, a bearing I8 for which is preferably provided in the motor base i2,

Secured at its upper end to the motor base t2 is a heavy stationary tubing 2d which extends downwardly into the tank li and is connected at its lower end to a centrifugal pump 2i so as to suspend said pump von said tubing.

vThe pump 2i includes a casing 25 which may belformed of two parts as shown to provide an vimpeller chamber 2t there being an impeller bearing 21 formed centrally in the bottom of said casing. The chamber 26 is enlarged at one side as shown in Fig. 4 to provide a discharge port 28 which leads to avthreaded opening 29 into which the lower end of a liquid discharge pipe 30 may be screwed downwardly. i.

l The impeller chamber 26 has a central/bore 35 which extends upwardly through the upper half of the casing 25. Formed on the casingv 25 about the upper end of the -bore is an annular collar 36 having a curved upwardly disposed surface 31 as shownv in cross section in Fig. 2. 'Formed integral with the casing collar 36 and extending upwardlysubstantially vertically therefrom in.

circumferentially 'spaced relation is a series of struts 38.

These struts must -be suiiciently strong to supf port the pump 2i and they have the added function of directing liquid Lthrough openings dil formed therebetween into an admission chamber 4I which is disposed centrally in communication with the bore 35 and surrounded by the struts 38.

The preferred cross sectional contour. of the struts 38 and the radially-opening passages lli disposed'therebetween ,is shown in Fig. 3. In

this preferred contour the strutsv38 are substantially "tear drop in cross section with the bulk of .their mass disposed outwardlyadja'cent the outer edge of the collar 36. The inner edges of the struts 38 areseen to be relatively sharp andas being formed by outwardly disposed concave side faces and inwardly disposed convex side faces 46,'. these faces coming together at inner thin sectional view taken on 'mthetank Il.

edges f the struts so as to be substantially tangent with the outer limits of the admission chamber I I vIt may readily be seen that the formation and dispositon of the struts 38 as clearly shown in Figs. 2 and 3 results in imparting a swirling motion to liquid entering the admission chamber Il through the passages 40. It may also be noted that while planes passing through the outer and inner edges of the struts 38 are disposed spirally in a clock-wise direction as seen in Fig. 3, the

bulk oi' the material in the struts 38 is preferu ably disposed between radial planes tangent with the side boundaries o1' the thickest portions of the l5 above and communicating with said throat, side struts. Viewed in this maner the inner portions of the struts 38 are seen to be turned in a clockwise direction from the balance oi' the material inthe struts.

The upper ends oi the struts 38 are integral with a bonnet 50 having a bearing 5l and which is connected by cap screws 52 to the lower end of the tubing 20. The bottom face 53 of the bonnet 50 is preferably a shallowv inverted conical surface which provides a readyl escape for coalesced bubbles of vapor or gas separated from liquid in the admission chamber! i.

Rotatably mounted lin the impeller chamber 2-6 is an impeller 30 having a stud 6l extending axially downwardly therefrom into the bearing 21.

The shaft il extendsdownwardly through Vthe bearings I8- and 5I and is connected axially with the impeller 30. l

The construction pf the impeller 60 follows conventional design and includes the formation of spiral passages 62 which lead from a central liquid admission throat 63 downwardly and outwardly'to the periphery of the impeller. As clearly shown in Figal and 2`the throat 63 is formed.

in a neck 64 rotating in the bore 36. It opens upwardly directly intothe admission chamber Il and theupper end of this throat expands in diameter so that-its surface is contiguous to and tangent with the adjacent curved surface 3l of the casing collar 33.

The discharge pipe 30 extends upwardly through a suitable opening in the motor base i2 so that the entire unit I0 may be mounted in. the 4tank il as shown, without requiring the tank to be taken out of the ground or the making o! any alterations on the bottom. of the tank whatsoever.

Operation After the unit l0 has thus been installed and liquid in which vapor or'gas is occluded is delivered into the tank Il to cover the pumpA 2|,the motor ill is energized to rotate the shaft i1 and impeller 60. Rotation of the impeller sucks liq- -uid in through the passages 40, the admission chamber 4I, the impeller throat 63 and expels this liquid from the impeller throughthe spiralv passages32. This liquid is thus forced upwardly through the port 23 and discharge pipe 30 and conductedbythe latterv to the place where it is desired this'be delivered.

A fter the lliquidis thus sucked ,V inwardly through the passages it is given an extremely rapid and smooth rotational movement kas it en- In this manner subjected to a vortical a'ction whichseparates thevapors and gases and permits these to escape upwardly along the bonnet bottom 53 in large bubbles which then rise to the surface of 'the liquid J- 4 "1' N Having described the invention, I claim: 1. A vapor eliminating centrifugal pump comv prising: an impeller casing; an impeller rotatable on a vertical axis therein. said impeller having a 5 liquid admission throat opening axially upward- 1y: a vertical shaft connecting axially with said impeller; a plurality ofsubstantially vertical 'struts provided on said casing and extending upwardly therefrom; and a bonnet vertically superl0 yimposed above the portiomof said casing with faces of said struts in the direction ofrrotation oi' said impeller being concave and opposite side l faces thereof convex, said side faces where they n meet at the inner edges of said struts -being sub-- stantially tangential with the outer limits of said f chamber.

2. A vapor eliminating centrifugal pump comprising: an impeller casing; an impeller rotatable on a vertical axis therein, said impeller having a liquid admission throat opening axially upwardly; a vertical shaft connecting axially with said impeller; a plurality of substantially vertical struts provided on said casing and extending upwardly therefrom; and a bonnet vertically superimposed above the portion of said casing with which said struts connect, said bonnet being united with the upper ends of said struts, said struts being tear-drop in cross section wlh the bulklthereoidisposed adjacent their outer edges and with their innerthinner edge Portions inclined from the balance thereof in the direction ofrotation of said impeller.

3. In a centrifugal pump the combination of:

f an impeller casing; an impeller rotatable on a vertical axis therein, said impeller having a liquid admission throat opening axially upwardly; a shaft extending downwardly through said throat to said impeller for rotating the latter; a bonnet surrounding said shaft and vertically superposed above said casing; and a plurality of struts spaced circumferentially about and radially from,

said shaft to define an admission chamber lust above and opening downwardly into said throat, said struts uniting said casing with said bonnet,

'5 0 each of said struts having a comma-like cross section with the tail thereof contiguous with said admission chamber and turned in the direction traveled by the adjacent surface of said shaft.

JOHN B. WADE.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,714,784 yHollander May 28, 1929 1,981,965 Morgan Nov. 27, 19313 1,440,808 Wineman Jan. 2, 1923 1,734,507 Westling Nov. 5, 1929 2,178,994 Inglis Nov. '1, 1939 1,874,324 MacMeeken e Aug. 30, 1932 2,124,681 Jauch et al. July 26, V1936 FOREIGN v PATENTS Number Country Date 436,269 Germany Oct. 28, 1926 331,142 England June 26, 1930 652,740 Germany Nov. 6, 1937 France .e July '1, 193s 

